High Arctic plant community resists 15 years of experimental warming
Hudson, J. and Henry, G. 2010. Journal of Ecology 98:1035-1041
Abstract
1. Identifying plant communities that are resistant to climate change will be critical for developing accurate, wide-scale vegetation change predictions. Most northern plant communities, especially tundra, have shown strong responses to experimental and observed warming.
2. Experimental warming is a key tool for understanding vegetation responses to climate change. We used open-top chambers to passively warm an evergreen-shrub heath by 1.1-1.3 C for 15 years at Alexandra Fiord, Nunavut, Canada (79 N). In 1996, 2000 and 2007, we measured height, plant composition and abundance with a point-intercept method.
3. Experimental warming did not strongly affect vascular plant cover, canopy height or species diversity, but it did increase bryophyte cover by 6.3% and decrease lichen cover by 3.5%. Temporal changes in plant cover were more frequent and of greater magnitude than changes due to experimental warming.
4. Synthesis. This evergreen-shrub heath continues to exhibit community-level resistance to long term experimental warming, in contrast to most Arctic plant communities. Our findings support the view that only substantial climatic changes will alter unproductive ecosystems.
Key Words
climate change experimental warming International Tundra Experiment open-top chamber passive warming resistance tundra vegetation change
